Optimal regulation of cathodic protection plant operation on the basis of reliability and residual life

Corrosion of steel underground pipelines significantly reduces the service life, leading them to an emergency condition, in which further operation is impossible. The main methods of protecting such pipelines are insulating coatings and electrochemical protection.
Determination of the optimal operating parameters of the electrochemical protection system allows to increase the service life of protected objects, due to a decrease in the load on working objects. These approaches are mainly aimed at reducing energy consumption by determining their optimal output parameters of electrochemical protection equipment, subject to compliance with the requirements of RD for permissible values of the protective potential. However, optimal control algorithms do not directly take into account the actual technical state of the system and cannot provide information about its reliability.
The average life of most existing pipelines is more than 20 years. The actual corrosion protection characteristics of such pipelines are significantly reduced in comparison with the initial. In view of this, there is a need to determine the reliability of the electrochemical protection system. Proposed methods for determining and evaluating the reliability indicators of electrochemical protection systems are aimed at building Markov models of the reliability of the object under study and determining it s availability factor.
The implementation of optimal control algorithms in conjunction with methods for assessing the reliability of electrochemical protection systems can make it possible to determine the time of trouble-free operation and identify the most “vulnerable” elements of the system.

1. Corrosion Protection. Design ingesis of electrochemical protection of underground structures. (2020). STO Gazprom 9.2-003- 2020. Moscow: VNIIGAZ LLC.

2. Reliability in technology. Terms and definitions. (2015). GOST 27-002-2015. St. Petersburg: VNIIGAZ LLC.

3. Nikulin, S. A. (2015). Improving the efficiency of preventing corrosion of oil and gas pipelines on the basis of optimal regulation of the modes of operation of cathode protection stations. Ph. D. dissertation. Ukhta.

4. Reliability in technology. Application of Markov methods. (2019). GOST R MAC 61165- 2019. Moscow: Izdatelstvo Standardinform.

5. Viktorova, V. S. (2013). Models and methods for calculating the reliability of technical systems / V.S. Viktorova, A.S. Stepanyants – Moscow: Higher school.

6. Viktorova, V. S. (2011). Dynamic fault trees / V.S. Viktorova, A.S. Stepanyants. Reliability, (3), 20-32.

7. Sabanov, S. V., Nikulin, S. A., Karnavsky , E. L. (2020). Determination of the priority of putting the anticorrosion protection equipment into repair at the gas pipeline section in conditions of limited funding. Theory and Practice of Corrosion Protection, 25(2), 7-17. doi: 10.31615/j. corros.prot.2020.96.2-1

8. Karnavsky, E. L., Nikulin, S. A. (2016). Definition of the residual resource of the materials of the PPC system: Karnavsky E.L., Nikulin S. A. Gas industry (737), 14-17.